This invention relates to electrical power generation systems in general and in particular to electrical power generation systems which are suitable for utilization in oilfield applications.
In the prior art there are many methods utilized to perform the work of removing oil and other petrochemical deposits from pools or reservoirs beneath the earth's surface. These methods typically include submersible pumps, pumpjacks and other methods of lifting fluid from beneath the surface. These devices are generally operated utilizing either electric power from an existing electrical power distribution system or by an internal combustion engine powered by gasoline or in some cases by the casing gas present in the wellhead in certain wells.
Each of these known methods has its advantages and disadvantages. For example, electrically powered systems are generally reliable and will effectively lift fluid from beneath the earth's surface as long as electric power is available. However, the cost of generating electrical power is rapidly increasing and the amount necessary to operate a large number of oilfield pumps can generate an extremely high utility bill.
In those applications in which casing gas is present in the wellhead, it is sometimes efficient to utilize this gas to power an internal combustion engine to drive a pump or generator; however, the variations in flow, pressure and availability of casing gas result in this method being not a dependable source of energy. With such systems periods of low pressure may result in downtime during which no oil is pumped from the well.
Therefore, there exists a need for a power generation system which combines the economic advantages of the gas engine system with the relative reliability of the electrical systems.